Feeding mechanism for sewing-machines



A. J. WOHLPART. FEEDING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED JAN. 7, 1915.

Patented July 19, 1921.

3 SHEETSSHEET 1- A. J. WOHLPART. FEEDING MECHANISM FOR SEWING MACHINES.

- APPLICATION FILED mm], 1915. 1,384,797. Patented July 19, 1921.

3 SHEETS-SHEET 2- it; a.

A. .I. WOHLPART. FEEDING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED JAN- 7, I915. 1,384,797.

Patented July 19, 1921.

3 SHEETS-SHEET 3- umrE-o :STATES PATENT OFFICE.

'AUGUST IzWOHLPABT, OF NEW YORK, N. Y., -ASSIGNOR T0 UNIONSPECIALMACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

FEEDING MECHANISM FOR SEWING-MACHINES.

Specification of Letters Patent. "Patented J [11y 19, 1921.

Application filed January 7, 1915. Serial No, 944.

'lVlechanism for Sewing-Machines, of which thefollowingis a description,reference being had to the accompanying drawing and to the-figures ofreference marked thereon. The invention relates to new and usefulimprovements in .feeding mechanisms for sewing machines, and moreparticularly to a feeding mechanism for a sewing machine having awork-supporting arm in which the feedingmechanism is located, andconsists of main and auxiliaryfeed dogs which may be given adifferential movement relative to each other during the feeding of thematerial. 7

An object of the invention is toprovide a feedingmechanism of the abovecharacter with means for ,varying the differential movement of thefeeddogs relative to each other, or for causing said feed dogs-t0 lQve inunison, which means may-be controlled-by the operator without stoppingthe stitching mechanism.

A further object of the invention is to provide a feeding mechanism ofthe above character with means for supporting the auxiliary feed dog,whereby the position of said feed dog relative to the surface of thework-supportingarm may be adjusted.

These and other objects will in part be obvious, and will in part behereinafter more fully described.

In the drawings which show by wayof illustration one embodiment of theinvention,-

Figure 1 is a side. elevation with parts broken away and arts insection, showing a machine embodying my improvements;

Fig. 2 is *a view partly in topplan and partly in horizontal section.showing a portion of the feeding mechanism and the devices forregulatingthe same;

Fig. 3 is'an enlarged-view partly in side elevation and partlyin,section,sh0wing the controlling means forvarying-the throw of thefeed dogs;

Fig. 4 is a'similar view show-111g the con trolling means shifted toadifferent-position;

Fig. 5 is a detail partly in section and partly in endelevation, showingthe controlling means and the position of the same relative to thestandard of the machine.

Fig. 6 is a detail on a small scale, showingthe trea'dl'e connection forshifting the controlling lever; I

Fig. 7 is an enlarged detail in section, showing th two feed dogs andthe manner or supporting the same.

Fig. 8 is an end view of the same.

The invention consists generally in pro- Vidinga sewing machinehaving astandard and a work-supporting arm with a feeding mechanism which islocated in said workvsupporting arm. Said feeding mechanism includes amain feed dog and an auxiliary feed dog. The auxiliary feed dog isoperated through the mechanism which reciprocatesthe main feeddog byintermediate devices which may give to the auxiliary feed dog adifferential movement relativeto the main feed dog. These devices maybeadjusted so the two feed dogs willmove in unison.

ing the throw or for causing saideauxiliary feed dog to move in unisonwith themain feed dog. This manual control .may be effected withoutstopping the stitching mechanism.

Referring more in detail tothe drawings, I haveshownmy improved feedingmechanism as embodied in a sewing machine consisting of a standard 1, onwhich is mounted an overhanging arm 2. A needle bar 3-reciprocates .insaid overhanging arm and carriesneedles 4, 4. The needle bar isreciprocatedby the usual needle lever from an eccentric on the mainshaft 5. "This main shaft extends crosswise of the standard. Thisneedle-operated mechanism is of These intermediate devices whichglvethe-differential throw tothe auxiliary feed dog, may be manuallyshiftedfor varythe well known construction in this type of thework-supporting arm. This feeding mechanism consists of a main feed dog11 and an auxiliary feed dog 12.

Extending lengthwise from the arm is a main feed bar 13. The mainfeedbar 13 eccentric on the main shaft 5. As this main shaft 5 rotates,the arm 18 will be oscillated,

and this in turn will vibrate the feed rocker back and forth. Said feedrocker carries a slotted bracket 20. A link 21 is adjustably connectedto said slotted bracket at one end, and atits other end is pivotallyattached to the feed bar 13. As this feed rocker moves back andforth,-the link2l will cause the feed bar to reciprocate lengthwise insaid work-supporting arm.

The feed bar adjacent the main feed dog is in the form of a shaft, andon this shaft is a sleeve 22, which sleevecarries the auxiliary feeddog. At the forward end of the sleeve22 is a bracket 23, and theauxiliary feed dog, (which as herein shownis inthree sections,) isadjustably attached to this bracket by suitable screws 24. By looseningthe screws 24, the auxiliary feed dog may be raised and lowered and theposition of the same relativ to the surface of ,the work-supporting armvaried.

A lever 25 extends lengthwise of the worksupporting arm andv isfulcrumed at 26 on a bracket carried by said arm. At the forward end ofsaid. lever, there is a link 27 which link at its upper end is pivotedto the sleeve 22 carrying the auxiliary feed dog. The lever 25 extendsrearwardly into the standard, and. is pivotally connectedto a link 28,which cooperates with an eccentric 29 on the main shaft 5. As the mainshaft 5 rotates, this eccentric will. oscillate the lever 25, raisingand. lowering the front end of the same, which in turn raises and lowersthe sleeve 22 and the feed bar which extends through the same. .Thisgives the up and down movements to both feed dogs. -While the sleeve 22moves up and down with the feed bar13, it is free to move endwise onsaid feed bar.

Pivoted to the feed bar at 30 is an auxiliary feed rocker .31. Thisauxiliary feed rocker 31 has a rearwardly extending arm 32 which ispivotally connected to a link The link 33 at its lower end is attachedto an arm 34:, fixed to the cross shaft 17, carrying the main feedrocker 16. As this main feed rocker oscillates, the arm .34: is moved upand down and through the link 38 will rock the auxiliary feed rocker 31.Said auxiliary feed rocker 31 is provided with a second arm. 35,extending downwardly from the fulcrum of the feed rocker and formed witha slot'36.

A link 37 is pivoted at one end to a stud which'is adjustable up anddown in the slot 36, while the other end of this linkis pivoted at 38tothe sleeve 22. This stud 35 may be moved over the fulcrum point of theauxiliary feed rocker, as show-11' in Fig. 4, and whenso positioned theoscillating movements ofthe auxiliary feed rocker will have no effectupon the link 37. o I V The pivot stud 35 maybe shifted along the slotto any desired position, or to the lower end of the slot, as shown inFigs. 1

and 3, and when in this position, theoscilla: tions of the auxiliaryfeed rocker through the link 87 willcause the sleeve 22'to move endwiseon the feed bar13. It is to be noted that this auxiliary feed. rocker ispivoted on the main feedbar, and, therefore, bodily moves back and forthwith the feed bar in addition to the oscillating movements imparted to,the auxiliary feed rocker through the link 33. The feeding mechanismabove described per 86 forms nopart of my present invention, except asit embodies a differential feeding mechanism whichmay be controlled bythe mechanism hereinafter described.

j The link 37, which gives to the sleeve 22 its movements relative tothe main feed bar, may be shifted so that this throw of the sleeve 22relativeto the main feed bar may be varied, by. means of a lever 39,which is freely pivoted on the cross shaft 17. This lever is connectedby a link 40to the link 37. The lever at the rear end is connected to arock lever 41 by a link 42. I The rock lever 41 is pivoted at 13' to thestandard 1 of the machine.

A spring 44 is attached to one arm of the rock lever 41-1 at one end,and to a suitable lug .5 on the standard at its other end. This springnormally shifts the. rock lever. 41, so as, to depress the .rear end ofthe lever 39,

.and this through the link 4.0wi11 raise the link 37 to neutralposition,that is, with the pivot stud 35 overthe fulcrum of the auxiliary feedrocker. The rock lever 41 may be moved in the opposite direction by achain 4:6, which may be connected to a treadle 47, see Fig. 6,

In order to limit themovements of the rock lever 41, I have providedsaid rock lever with two spaced arms 48 and 49, each of which isprovided withan adjustable screw 50. A pin 51 earriedby the standard ofthe machine, serves as an abutment for these steps and limits themovements of the rock lever 41. I, I I 1 From the above description, itwill be apparent that I have provided afeeding mechanism wherein a mainfeed bar carries a main feed dog,'and said main feed bar is reciprocatedback and forth longitudinally dog and the mainfeed dog at each feedingaction will feed the material equal distances, or may be given adifferential movement relative to said mam feed dog, that is, the

auxiliary feed dog will move the fabric a little faster than the mainfeed dog.

Furthermore, this differential feeding movement imparted to theauxiliary feed dog may be varied by depressing the treadle. lVhen thetreadle is depressed, the auxiliary feed dog will be given adifferential feeding movement. hen the treadle is released, the spring4A will shift the rock lever 41 to the position shown in Fig. 4, andthen said auxiliary feed dog will move in unison with the main feed dog.This shifting or controlling of the movements of the auxiliary feed dogmay be quickly accomplished, without stopping the stitching mechanism.It is noted that the treadle controlled lever is mounted on'the standardand not on the work supporting arm, and, therefore, the work supportingarm is left entirely free to receive the garment.

The auxiliary feed'dog is located in front of the needles and engagesthe material and feeds the same to the needles, while the main feed dogis located substantially in rear of the needles. This machine isparticularly adapted for stitching elastic material and when operatingupon such material, the auxiliary feed dog may begiven a slightly fasterfeeding movement than the main feed dog, thus crowding the elasticmaterial to the needles to prevent the stretching of the same.

it is obviousthat minor changes in the construction and arrangement ofthe parts may be made, without departing from the spirit of theinvention, as set forth in the appended claims.

Having thus described my invention, what I claim as new and desire tose'cureby Letters Patent, is

1. In a sewing machine, the combination of'a standard, a work-supportingarm projecting therefrom and a feeding mechanism located within saidwork-supporting arm for feeding the material longitudinally thereof,said feeding mechanism including a main feed bar, a feed dog carriedthereby, a sleeve embracing said main feed barand capable of endwisemovement thereon, an auxiliary feed dog carried by said sleeve, meansfor moving said sleeve endwise in unison with the main feed bar or forgiving a differential movement to said sleeve, means under thecontrol'of the operator for giving to said sleeve said differentialmovement or'for causing the same to move in unison with the main feedbar, said last named means ineluding a lever located in saidwork-supporting arm, a rock lever pivoted to said stand ard andconnected to said lever, and a manually-operated member connected tosaid rock lever.

2. In a sewing machine, the combination of a standard, a work-supportingarm projecting therefrom and a feeding mechanism located within saidwork-supporting arm for feeding the material longitudinally thereof,said feedin mechanism including a main feed bar, a feed dog carriedthereby, a sleeve embracing said main feed bar and capable of endwisemovement thereon, an auxiliary feed dog carried by said sleeve, meansfor moving said sleeve endwise in unison with the main feed bar or forgiving a differential movement to said sleeve, means under the controlof the operator for giving to said sleeve said differential movement orfor causing the same to move in unison with the main feed bar, said lastnamed means including a lever located in said work-supporting arm, arock lever pivoted to said standard and connected to said lever, amanually-operated member connected to said rock lever, spaced stopscarried by said rock shaft and an abutment mounted on said standard withwhich said stops cooperate.

In a sewing machine, the combination of a standard, a work-supportingarm projecting therefrom and a feeding mechanism located within saidwork-supporting arm for feeding the n'iaterial longitudinally thereof,said feeding mechanism including a main feed bar, a feeddog carriedthereby, a sleeve embracing said main feed bar and capable of endwisemovement thereon, an auxiliary feed dog carriedby said sleeve, means formoving said sleeve endwise in unison with the main feed bar or forgiving a differential movement to said sleeve, means under the controlof the operator for giving to said sleeve said differential movement orfor causing the same to move in unison with themain feed bar, said lastnamed means including a lever located in said \vorlr-supporting arm, arock lever pivoted to said standard and connected to said lover, aspring for moving said rock lever in one direction and a treadle formoving the rock lever in the other direction, and stops for limiting themovement of the rock lever in each direction.

4;. In a sewing machine, the combination of a standard, awork-supporting arm pro jecting therefrom and a'feeding mechanismlocated within said work-supporting arm for feeding the materiallongitudinally thereof, said feeding mechanism including a main feedbar, a feed dog carried thereby, a sleeve embracing said main feed barand'capable of endwise movement thereon, an auxiliary feed dog carriedby said sleeve, means for moving said sleeve endwise in unison with themain feed bar or for giving a differential movement to said sleeve,means under the control of the operator for giving to said sleeve saiddifferential movement or for causing the same to move in unison with themain feed bar, said last named means including a lever located in saidwork-supporting arm, a rock lever pivoted to said standard and connectedto said lever, a spring for moving said rock leverin one direction and atreadle for moving the rock lever in the other direction, spacedadjustable screws carried by said rock lever, and an abutment mounted onsaid standard with which said screws cooperate for limiting the movementof said rock lever in each direction.

5. In a sewing machine, the combination of a standard, a work-supportingarm projccting therefrom, a feed ng mechanism lo cated in saidwork-supporting arm for feeding the material longitudinally of said armand including a main feed bar, a feed dog carried thereby, an auxiliaryfeed bar and a feed dog carried thereby, a feed rocker for said mainfeedbar for moving the same end wise in said arm, an auxiliary feedrocker mounted on said main feed bar, means for oscillating saidauxiliary feed rocker from said main feed rocker, said auxiliary feedrocker having a slotted arm, a link for connecting said slotted arm tothe auxiliary feed bar, said link being shiftable along said slotforvarying the throw imparted to said auxiliary feed bar or for causingsaid auxiliary feed bar to move in unison with the main feed bar, andmeans under the control of the operator for shifting said linkconnection with the auxiliary feed rocker without stopping the stitchingmechanism, including a lever located in said worksupporting arm andprojecting into the standard, a link connecting the end of the leverwith said link which operates the auxiliary feed bar, and means wherebysaid 1 lever may be shifted by the operator.

6. In a sewing machine, the combination of a standard, a.work-supportingarm projecting therefrom, a feeding mechanism loeated in saidwork-supporting arm for feeding the material longitudinallyof said armand including a main feed bar, a feed dog carried thereby, anauxiliaryfeed bar and a feed dog carried thereby, a feed rocker for said mainfeed bar for moving the same endwise in said arm, an auxiliary feedrocker mounted on said main feed bar, means for oscillatingsaidauxiliary feed rocker from said main feed rocker, said auxiliaryfeed rocker having a slotted arm, a link for connecting said slotted armto the auxiliary feed bar, said link being shiftable along saidslotsforyarying the throw imparted to said said lever,a treadleconnected to theother end of said rock lever, a spring for moving therock lever in one direction, and stops for limiting the movement of therock lever in each direction.

7. A sewing machine including in combination a standard, ahorizontalwork supporting arm carried by and projecting from said standard, afeeding mechanism comprisinga main feed supporting member ex tendinglongitudinally of and located within 7 said work supporting arm, amainfeed dog carried thereby, an auxiliary feed supporting memberlocated within said work supporting arm, an auxiliary feed dog carriedthereby, means for raising and lowering said feed dog supportingmembers, means for moving said main feed dog supporting member backand-forth, means formoving said auxiliary feed dog supporting memberback and forth and for giving thereto a differential movement relativeto the main feed dog, and means under the control. of the operator forvarying'the differential movement given to the auxiliary feed dogwhereby said auxiliary feed dog may be caused to move in unison with themain feed dog and without stopping the stitching mechanism, saidlast-named means including a lever located within said work sup portingarm, a rock lever pivoted to the standard and connected to saidfirst-named lever, and a manually operated lever connected to said rocklever.

- 8. A sewing machine including in combination, a standard, a horizontalwork supporting arm carried by and projecting from said standard, ,afeeding mechanism comprising a main feed supporting member extendinglongitudinally of-and located within said work supporting arm, a mainfeed dog carried thereby, an auxiliary feed. supporting' member locatedwithin said work supporting arm, an auxiliary feed dog carried thereby,means for raising and lowering said feed dog supporting members, meansfor moving said main feed dog supporting member back and forth, meansfor movingsaid v auxiliary feed dog supporting member back andforth andfor giving thereto, a differential movement relative to the main feeddog, and means under the control of the operator for varying thedifferential movement given to the auxiliary feed dog the rock lever,and an abutment mounted whereby said auxiliary feed dog may be on thestandard with which said stops coopcaused to move in unison with themain feed ei'ate. dog and Without stopping the stitching In testimonywhereof, I aflix my signa- 5 mechanism, said last-nalmed meansiliilcludture in the presence of two Witnesses.

ing a lever located Wit iin said Wor supporting arm, a rock leverpivoted to the AUGUST VOIILPART' standard and connected to saidfirst-named lVitnesses: lever, a manually operated lever connected F. G.MERE, 10 to said rock lever, spaced stops carried by WV. BLANOHARD.

